Improved ion detection sensitivity in mass spectrometry imaging using tapping-mode scanning probe electrospray ionization to visualize localized lipids in mouse testes.

Mass spectrometry imaging (MSI) is a promising analytical method to visualize the distribution of lipids in biological tissues. To clarify the relationship between cellular distribution and lipid types in a tissue, it is crucial to achieve both an improvement in ion detection sensitivity and a reduction in the ionization area. We report methods for improving the efficiency of ion transfer to a mass spectrometer and miniaturizing the extraction area of a sample for tapping-mode scanning probe electrospray ionization (t-SPESI), atmospheric pressure sampling, and ionization methods.

Astrocyte aquaporin mediates a tonic water efflux maintaining brain homeostasis.

Brain water homeostasis not only provides a physical protection, but also determines the diffusion of chemical molecules key for information processing and metabolic stability. As a major type of glia in brain parenchyma, astrocytes are the dominant cell type expressing aquaporin water channel. How astrocyte aquaporin contributes to brain water homeostasis in basal physiology remains to be understood.

Induction of drug metabolizing enzyme and drug transporter expression by antifungal triazole pesticides in human HepaSH hepatocytes.

Triazole pesticides are widely used fungicides, to which humans are rather highly exposed. They are known to activate drug-sensing receptors regulating expression of hepatic drug metabolizing enzymes and drug transporters, thus suggesting that the hepatic drug detoxification system is modified by these agrochemicals. To investigate this hypothesis, the effects of 9 triazole fungicides towards expression of drug metabolizing enzymes and transporters were characterized in cultured human HepaSH cells, that are human hepatocytes deriving from chimeric humanized liver TK-NOG mice.

Clemastine enhances exercise-induced motor improvement in hypoxic ischemic rats.

Neonatal hypoxic ischemia (HI) occurs owing to reduced cerebral oxygen levels and perfusion during the perinatal period. Brain injury after HI triggers neurological manifestations such as motor impairment, and the improvement of impaired brain function remains challenging. Recent studies suggest that cortical myelination plays a role in motor learning, but its involvement in motor improvement after HI injury is not well understood.

Bridging toxicological properties of environmental chemicals between animals and humans using healthy organoid systems.

The application of organoids derived from animal tissues and human-induced pluripotent stem cells to safety assessments of environmental chemicals has been introduced over the last decade. One of the objectives of this approach is to develop an alternative method for animal toxicological studies, while another is to focus on the local reactions of chemicals in each organ/tissue. One of the most important goals is bridging the toxicological properties of chemicals between animals and humans, which may be compared on a level playing field using healthy organoids derived from both animals and humans in vitro, excluding species difference in the absorption, distribution, metabolism, and excretion properties of chemicals in vivo.

Engraftment of human mesenchymal stem cells in a severely immunodeficient mouse.

The transplantation of human mesenchymal stromal/stem cells (hMSCs) has potential as a curative and permanent therapy for congenital skeletal diseases. However, the self-renewal and differentiation capacities of hMSCs markedly vary. Therefore, cell proliferation and trilineage differentiation capacities were tested in vitro to characterize hMSCs before their clinical use.

Brain morphological analysis in mice with hyperactivation of the hedgehog signaling pathway.

Hedgehog signaling is a highly conserved pathway that plays pivotal roles in morphogenesis, tumorigenesis, osteogenesis, and wound healing. Previous investigations in patients with Gorlin syndrome found low harm avoidance traits, and increased volumes in the cerebrum, cerebellum, and cerebral ventricles, suggesting the association between brain morphology and the constitutive hyperactivation of hedgehog signaling, while the changes of regional brain volumes in upregulated hedgehog signaling pathway remains unclear so far. Herein, we investigated comprehensive brain regional volumes using quantitative structural brain MRI, and identified increased volumes of amygdala, striatum, and pallidum on the global segmentation, and increased volumes of the lateral and medial parts of the central nucleus of the amygdala on the detail segmentation in heterozygous deletion mice.

Urinary bladder carcinogenic potential of 4,4'-methylenebis(2-chloroaniline) in humanized-liver mice.

Occupational exposure to 4,4'-methylenebis(2-chloroaniline) (MOCA) has been linked to an increased risk of bladder cancer among employees in Japanese plants, indicating its significance as a risk factor for urinary bladder cancer. To investigate the role of MOCA metabolism in bladder carcinogenesis, we administered MOCA to non-humanized (F1-TKm30 mice) and humanized-liver mice for 4 and 28 wk. We compared MOCA-induced changes in metabolic enzyme expression, metabolite formation, and effects on the urinary bladder epithelium in the 2 models.

Identification of gene mutations associated with the phenotype of short-limb mice emerging from a foundation colony of severely immunodeficient mice.

Here, we report the identification of causative genes for limb-shortening in individuals repeatedly found in a population of severely immunodeficient NOG mice maintained via sibling mating. First, we conducted a pedigree survey to determine whether limb-shortening was a recessive genetic trait and then identified it using a crossing test. Simultaneously, the symptoms were identified in detail using pathological analysis.

Production of a heterozygous exon skipping model of common marmosets using gene-editing technology.

Nonhuman primates (NHPs), which are closely related to humans, are useful in biomedical research, and an increasing number of NHP disease models have been reported using gene editing. However, many disease-related genes cause perinatal death when manipulated homozygously by gene editing. In addition, NHP resources, which are limited, should be efficiently used.

Cerebrospinal Fluid Dynamics Analysis Using Time-Spatial Labeling Inversion Pulse (Time-SLIP) Magnetic Resonance Imaging in Mice.

Abnormalities in cerebrospinal fluid (CSF) dynamics cause diverse conditions, such as hydrocephalus, but the underlying mechanism is still unknown. Methods to study CSF dynamics in small animals have not been established due to the lack of an evaluation system. Therefore, the purpose of this research study is to establish the time-spatial labeling inversion pulse (Time-SLIP) MRI technique for the evaluation of CSF dynamics in mice.

Genome editing using type I-E CRISPR-Cas3 in mice and rat zygotes.

The type I CRISPR system has recently emerged as a promising tool, especially for large-scale genomic modification, but its application to generate model animals by editing zygotes had not been established. In this study, we demonstrate genome editing in zygotes using the type I-E CRISPR-Cas3 system, which efficiently generates deletions of several thousand base pairs at targeted loci in mice with 40%-70% editing efficiency without off-target mutations. To overcome the difficulties associated with detecting the variable deletions, we used a newly long-read sequencing-based multiplex genotyping approach.

A Novel Immunodeficient Hyperglycemic Mouse Carrying the Ins1 Akita Mutation for Xenogeneic Islet Cell Transplantation.

Background: For patients who have difficulty controlling blood glucose even with insulin administration, xenogeneic islet cells, including human stem cell-derived pancreatic islets (hSC-islet) and porcine islets, have garnered attention as potential solutions to challenges associated with donor shortages. For the development of diabetes treatment modalities that use cell transplantation therapy, it is essential to evaluate the efficacy and safety of transplanted cells using experimental animals over the long term.

Methods: We developed permanent diabetic immune-deficient mice by introducing the Akita (C96Y) mutation into the rodent-specific Insulin1 gene of NOD/Shi-scid IL2rγcnull (NOG) mice (Ins1C96Y/C96Y NOG).

Development of a noninvasive olfactory stimulation fMRI system in marmosets.

Olfactory dysfunction is associated with aging and the earliest stages of neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases; it is thought to be an early biomarker of cognitive decline. In marmosets, a small non-human primate model used in brain research, olfactory pathway activity during olfactory stimulation has not been well studied because of the difficulty in clearly switching olfactory stimuli inside a narrow MRI. Here, we developed an olfactory-stimulated fMRI system using a small-aperture MRI machine.

Pierisin, Cytotoxic and Apoptosis-Inducing DNA ADP-Ribosylating Protein in Cabbage Butterfly.

Pierisin-1 was serendipitously discovered as a strong cytotoxic and apoptosis-inducing protein from pupae of the cabbage butterfly against cancer cell lines. This 98-kDa protein consists of the N-terminal region (27 kDa) and C-terminal region (71 kDa), and analysis of their biological function revealed that pierisin-1 binds to cell surface glycosphingolipids on the C-terminal side, is taken up into the cell, and is cleaved to N- and C-terminal portions, where the N-terminal portion mono-ADP-ribosylates the guanine base of DNA in the presence of NAD to induce cellular genetic mutation and apoptosis. Unlike other ADP-ribosyltransferases, pieisin-1 was first found to exhibit DNA mono-ADP-ribosylating activity and show anti-cancer activity in vitro and in vivo against various cancer cell lines.

Improvement of multilineage hematopoiesis in hematopoietic stem cell-transferred c-kit mutant NOG-EXL humanized mice.

Human hematopoietic stem cell (HSC)-transferred humanized mice are valuable models for exploring human hematology and immunology. However, sufficient recapitulation of human hematopoiesis in mice requires large quantities of enriched human CD34 HSCs and total-body irradiation for adequate engraftment. Recently, we generated a NOG mouse strain with a point mutation in the c-kit tyrosine kinase domain (W41 mutant; NOGW mice).

Liposome-encapsulated progesterone efficiently suppresses B-lineage cell proliferation.

Progesterone suppresses several ancient pathways in a concentration-dependent manner. Based on these characteristics, progesterone is considered a candidate anticancer drug. However, the concentration of progesterone used for therapy should be higher than the physiological concentration, which makes it difficult to develop progesterone-based anticancer drugs.

and Induction of Cytochrome P450 3A4 by Thalidomide in Humanized-Liver Mice and Experimental Human Hepatocyte HepaSH cells.

Autoinduction of cytochrome P450 (P450) 3A4-mediated metabolism of thalidomide was investigated in humanized-liver mice and human hepatocyte-derived HepaSH cells. The mean plasma ratios of 5-hydroxythalidomide and glutathione adducts to thalidomide were significantly induced (3.5- and 6.

PRMT1 Sustains De Novo Fatty Acid Synthesis by Methylating PHGDH to Drive Chemoresistance in Triple-Negative Breast Cancer.

Unlabelled: Triple-negative breast cancer (TNBC) chemoresistance hampers the ability to effectively treat patients. Identification of mechanisms driving chemoresistance can lead to strategies to improve treatment. Here, we revealed that protein arginine methyltransferase-1 (PRMT1) simultaneously methylates D-3-phosphoglycerate dehydrogenase (PHGDH), a critical enzyme in serine synthesis, and the glycolytic enzymes PFKFB3 and PKM2 in TNBC cells.